hgext/narrow/narrowdirstate.py

phases: sparsify phase lists

When the internal and archived phase was added, allphase became a large,
sparsely populated list. This dramatically increased the number of
lookup operations for public relations in `phasecache.phase`. As a first
step, define allphases and related lists explicitly to contain only the
actual phases. Make phasenames a dictionary and create corresponding
dictionaries for mapping phase names back to numbers. Adjust various
list to be sparse as well with the exception of phaseroots and phasesets
members of phasecache. Keep those as a separate step as it involves
changes to the C module.

Differential Revision: https://phab.mercurial-scm.org/D8697

# narrowdirstate.py - extensions to mercurial dirstate to support narrow clones
#
# Copyright 2017 Google, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

from mercurial.i18n import _
from mercurial import error


def wrapdirstate(repo, dirstate):
    """Add narrow spec dirstate ignore, block changes outside narrow spec."""

    def _editfunc(fn):
        def _wrapper(self, *args, **kwargs):
            narrowmatch = repo.narrowmatch()
            for f in args:
                if f is not None and not narrowmatch(f) and f not in self:
                    raise error.Abort(
                        _(
                            b"cannot track '%s' - it is outside "
                            + b"the narrow clone"
                        )
                        % f
                    )
            return fn(self, *args, **kwargs)

        return _wrapper

    class narrowdirstate(dirstate.__class__):
        # Prevent adding/editing/copying/deleting files that are outside the
        # sparse checkout
        @_editfunc
        def normal(self, *args, **kwargs):
            return super(narrowdirstate, self).normal(*args, **kwargs)

        @_editfunc
        def add(self, *args):
            return super(narrowdirstate, self).add(*args)

        @_editfunc
        def normallookup(self, *args):
            return super(narrowdirstate, self).normallookup(*args)

        @_editfunc
        def copy(self, *args):
            return super(narrowdirstate, self).copy(*args)

        @_editfunc
        def remove(self, *args):
            return super(narrowdirstate, self).remove(*args)

        @_editfunc
        def merge(self, *args):
            return super(narrowdirstate, self).merge(*args)

        def rebuild(self, parent, allfiles, changedfiles=None):
            if changedfiles is None:
                # Rebuilding entire dirstate, let's filter allfiles to match the
                # narrowspec.
                allfiles = [f for f in allfiles if repo.narrowmatch()(f)]
            super(narrowdirstate, self).rebuild(parent, allfiles, changedfiles)

    dirstate.__class__ = narrowdirstate
    return dirstate